Handheld Laser Leaf Area Meter

The CI-203 Handheld Laser Leaf Area Meter is a highly portable laser scanner ideal for rapid and non-destructive leaf area measurement in any location

Measurements are made easily by sweeping the scanner over a leaf to yield seven different parameters: area, width, length, perimeter, shape factor, aspect ratio, and void count.

Researchers can use the CI-203 to make non-destructive measurements on leaves of living plants, enabling data collection on a leaf or plant throughout its life span. Graphical outline of the leaf shape is provided upon completing a scan, which provides verification that measurements are calculated accurately on even the most intricate leaf shapes. Built-in GPS tagging adds a location for each data point, and the removable Wi-Fi SD card provides an easy and fast way to download data to your computer. For rapid measurement of detached leaves, the CI-203CA conveyor attachment makes a perfect complement to the CI-203.

Features

• Single-action Data Collection—sweep the CI-203 over a leaf to yield seven measurement parameters: area, width, length, perimeter, shape factor, ratio, and void count
• Non-destructive and multipurpose
• Flattens curled leaves to provide accurate measurements
• Durable, lightweight, and intuitive
• Graphic display of leaf outline for scan verification
• GPS tagging to provide location data for each measurement
• SD Card for data storage and transfer with virtually unlimited storage capacity
• USB charging and data download
• Rechargeable battery
• Measures objects up to 150 mm (254 mm with conveyor) wide and 25mm thick of virtually unlimited length
• Conveyor Attachment (CI-203CA) is available for fast, whole plant destructive measurement in the field or lab
• No calibration required

How to use it

To measure leaf area, simply sweep the measuring wand over the leaf, and the CI-203 instantly scans and calculates the leaf area, width, length, perimeter, shape factor, aspect ratio and void count.

• The CI-203 is flexible as well as fast: use in the field to measure living leaves on plants one-by-one, or add the conveyor attachment and measure hundreds of individual detached leaves at a time.
• The CI-203 stores over 15,000 data points, and displays data on the LCD screen. Download measurements to a computer later for further analysis via the SD card.

Theory of operation

The CI-203 collects length, width, perimeter, and area measurements directly using a combination of a sweeping laser beam and an optical motion sensor. After activating the device by pressing the <start> key, a low energy laser beam sweeps across the laser window 500 times per second at a rate of 150 m/s. As the user moves the CI-203 wand down the leaf, an optical sensor records the motion, and the onboard processing unit collects the data. Each laser sweep uses the optical sensor data to correctly accumulate the area and perimeter measurements. When the optical sensor detects that vertical motion has stopped, the laser subsystem stops taking measurements and the processing unit computes and posts the final results.

The perimeter increment is calculated and added to the perimeter accumulator. The perimeter increment is calculated using the function:

Computing Ratio and Shape Factor

Aspect ratio and shape factor information can be easily calculated from the other information gathered. These derived quantities are calculated whenever necessary for the purposes of display or data dumping. The calculations used are shown below.

Aspect ratio is the ratio of the leaf length to its maximum width. It can be calculated from the equation:

Shape factor is the ratio of the leaf area to the leaf perimeter, corrected so that the shape factor of a circle is equal to 1. It can be calculated from the equation:

What's in the box

• Laser leaf area meter main unit
• Internal battery
• Battery charger
• RS232 cable
• Communication software
• Operating manual
• Hard-shell instrument carrying case